Picture frame



FIG. 1 is a front elevational view of a picture frame showing our new design;

FIG. 2 is a side elevational view thereof, the opposite side being symmetrical;

FIG. 3 is a rear elevational view thereof; and

FIG. 4 is a top plan view thereof, the bottom plan view being symmetrical. 

The ornamental design for a picture frame, substantially as shown and described. 